Femtosecond studies of electron capture times in InGaN/GaN multiple quantum wells

Subpicosecond time-resolved differential transmission spectroscopy has been used to investigate the carrier density and temperature dependence of the quantum well electron capture time of blue-emitting InGaN/GaN multiple quantum well structures. It is found that the capture time varies significantly with both temperature and carrier density, the latter effect being consistent with carrier-induced band bending or increased carrier-carrier scattering. At room temperature, the electron capture time is in the range 0.4-0.8 ps for carrier densities less than or equal to5x10(18) cm(-3). (C) 2004 American Institute of Physics.